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Just some thougts about chillers

Well, i have fighted against a "yurk" chiller (loaded with R407C, yes i hate that refrigerant) that's trippin' on the freeze guard at one circuit, +3c (okay it'ts pure water on the cold side, a +12c/+8c system) Both circuits is a little underfilled, just about to flash in the sight glass.

However.... Suspicious about flow issues. Both circs is running with almost same values (+3c evap/+40c cond) but the circ thats trippin on freeze guard is running with deltaT 7c in/out on the water side, +3c subcool, +4c superheat, the other circ is +4c sub, +5 superheat and 5c deltaT in/out water side (yup it's plate heat exchangers), my service leader meaned that I would get a lower deltaT on the "problem circ" if I refilled it with refrigerant. But in my book... I would get a higher deltaT if its "Topped up" with missing ref., to get a lower dT, remove some ref. you get less effiency. I know that's its more factors that's making sense. But now. Just focusing on the ref. filling...

1) Why do you hate 407C? It's just a blended refrigerant - it hasn't done anything to you, has it?
2) Sounds like you may have heat transfer issues. Probably be a good idea to look at flow first, obstruction next, depending on how the waterside is piped.
3) Don't want to be the "ugly American", but since this is a U.S. based forum, you might want to convert your temps to °F before posting. I, for one, won't go to any great lengths to do that for you, and I know a lot of others that feel the same, so you limit your assistance by using the metric system around here.

Don't want to be the "ugly American", but since this is a U.S. based forum, you might want to convert your temps to °F before posting. I, for one, won't go to any great lengths to do that for you, and I know a lot of others that feel the same, so you limit your assistance by using the metric system around here.

X2.....

You will get a lot more responses if you convert to deg F. And you can't convert the delta T, you have to convert the 2 temps to deg F then figure delta T.

You will get a lot more responses if you convert to deg F. And you can't convert the delta T, you have to convert the 2 temps to deg F then figure delta T.

For delta T C to delta T F you can multiply by 1.8 or divide by 1.8 to go from delta F to Delta C. Living in a metric system country and communicating with US factories you get nowhere quick if you cannot be fluent in both languages

Well, i have fighted against a "yurk" chiller (loaded with R407C, yes i hate that refrigerant) that's trippin' on the freeze guard at one circuit, +37f (okay it'ts pure water on the cold side, a +53f/+46f system) Both circuits is a little underfilled, just about to flash in the sight glass.

However.... Suspicious about flow issues. Both circs is running with almost same values (+37f evap/+104f cond) but the circ thats trippin on freeze guard is running with deltaT 12,5f in/out on the water side, +5,5f subcool, +7f superheat, the other circ is +7,2f sub, +9 superheat and 5c deltaT in/out water side (yup it's plate heat exchangers), my service leader meaned that I would get a lower deltaT on the "problem circ" if I refilled it with refrigerant. But in my book... I would get a higher deltaT if its "Topped up" with missing ref., to get a lower dT, remove some ref. you get less effiency. I know that's its more factors that's making sense. But now. Just focusing on the ref. filling...

Oh... about my 407C issues... Ok, it might be a good ref. But not for me, i hate refs with big glide. I rather run 134a, 404A (or even better, 507) or 410A, ok 410 uses higer pressures, but that's no problem for me.

What kind of York chiller? Air cooled, water cooled, recip, screw, scroll? What's the model number? When you say "freeze guard at one circuit" what do you mean? I would think that would mean low water temp cutout, but that would shut down the whole chiller, not just a circuit. Do you mean "low evap refrigerant temp"?

water/water, hermetic reciprociating comp, ycwm 150. there's 2 circuits in the chiller, both circs has own plate heat exc's for cold and warm side, the only thing that ties them together is incoming and outgoing water pipes.

flow issues could be the problem. is the safety calibrated and tripping at the setpoint? how are the pressures as it is pulling the load down...stable and steady or losing control and 'wild'? keep in mind that R407c has a very high temperature glide and you must use the appropriate scale for liquid or vapor measurements. i wish we would all go metric...its a lot easier after you get used to it.